Loose leaf binder



Sept. 29, 1964 J. PoTTs 3,150,667

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United States Patent O 3,150,667 LOSE LEAF BINDER Kohn Potts, Chicago, Ill., assigner to Wilson-Jones Company, Chicago, lll., a corporation of Massachusetts Filed .lune 12, 1958, Ser. No. 741,556 2 Claims. (Cl. 129-4i) This invention relates to a loose leaf binder and to a sheet retaining prong mounted therein for holding a plurality of sheets provided with small apertures adjacent one edge thereof.

This application is a continuation-in-part of my prior copending application Serial No. 696,184, filed November 13, 1957, now abandoned.

Sheet retaining prongs of the general type to which the present invention is directed have heretofore generally been made of thin sheet metal, although some attempts have been made to use iiexible fiber board. The fiber prongs were not satisfactory and their use has been abandoned throughout the industry. The metal prongs are punched from narrow strips of tin plated stock. The tin plate is necessary to protect the prongs against corrosion. The use of noncorrosive metal or the use of ordinary sheet metal with subsequent plating of the prongs is not commercially feasible because of the cost factor.

Sheet retaining prongs of tin plated sheet metal have several serious disadvantages. The edges of the prongs that are sheared by the punching operation are not pro tected by the plating, and are subject to corrosion, The oxidation may cause parts of the prong fastener to stick together permanently. The sheared edge of the prong is sharp, and frequently cuts the fingers of users. The prongs become kinked each time they are bent, and it is very diicult to straighten them. After a prong has been used a considerable number of times it becomes increasingly diiiicult to pass it through the aperture of the compressor plate. The metal crystallizes and breaks after it has been bent repeatedly in the same area.

In accordance with the invention, two covers, preferably o fiber board, .are provided with apertures of the same size as the apertures in the sheets to be held between the covers. The apertures may be in the form of small slots, but usually are circular. The apertures of the covers are spaced to conform to the spacing of the apertures in the sheets so that they may be .aligned therewith. The covers may be provided with any desired number of apertures, but two apertures are sufficient for sheets having a binding edge up to fourteen inches in length. in binders for holding larger sheets, more apertures may be provided in each cover, with a separate sheet retaining prong for each aperture. Although a single compressor plate may be used with any desired number of prongs, it is preferred to arrange the apertures of each cover in pairs, and to provide a separate prong fastener mechanism, comprising two `sheet retaining prongs and a compressor plate, for each pair of apertures in the covers.

The sheets may be provided with the same number of apertures as each of the covers, but in the case of sheets adapted for use in pin feed tabulating machines, the sheets are provided with continuous rows of uniformly spaced apertures along the entire length of the binding edge of the sheet. The apertures in each cover must be some multiple of the spacing between adjacent apertures of the sheets to permit proper vertical alignment of the apertures of the sheets and the covers. The specific ,ldb'? Patented Sept. 29, 1554 ice spacing between the apertures of the cover depends upon the length of the binding edge of the sheets.

The sheet retaining prongs are molded of a tough, horny, resinous material characterized by ilexibity, high impact strength, and resistance to stretching. Examples of this material, are materials having the characteristics of nylon. The preferred material is nylon of the type having self-lubricating characteristics conventionally known as type 66 nylon. The resinous material is impervious to climatic conditions, and the prongs will not oxidize even in salt air.

The sheet retaining prong comprises a generally flattened tongue section adapted to extend through the vertically aligned apertures of the ysheets to be held in the binder, an integral enlarged head at one end adapted to be connected to one cover member adjacent the aperture through which the prong extends, and an integral cylindrical section adjacent said enlarged head. The cylindrical section extends through the aperture of the cover to which the prong is connected and its opposite end merges into the generally iiattened tongue section.

It will be noted that the word connected is used above in its broad sense as meaning closely associated, and will be used in the same broad sense throughout the specification yand claims. The cylindrical section provides additional strength in the area of the sheet retaining prong that is subjected to the greatest impact when a loaded binder is dropped on end edge of a cover member. The edges of the tongue section are smooth, and the sheet retaining prongs may be handled without danger of cutting the users fingers.

In normal usage, sheet retaining prongs are bent over compressor plates and held in such bent condition for long periods of time. Prongs made of resinous material, as hereinabove described, may be bent repeatedly in the same area without breakage or permanent deformation. The resilience of the resinous material urges the prongs back to their normal straight conditions, regardless of the length of time they have been held in bent position, immediately upon release of the holding means. The prongs may always be easily restored to completely straight condition merely by stroking them between the users fingers a few times.

It is an object of the invention to provide a loose leaf binder with sheet retaining prongs of resinous material.

lt is a further object of the invention to provide sheet retaining prongs of resinous material having a tongue section of generally flattened cross section adapted to extend through the apertures of sheets to be retained, thereon, and also extend through the apertures of a conventional prong fastener compressor plate by means of which it may be retained in bent position.

Another object of the invention is to provide a sheet retaining prong that will not oxidize, and may be bent repeatedly in the same area without breakage or permanent deformation.

Another object of the invention is to provide a sheet retaining prong having an integral enlarged head at one end for connecting it to a loose leaf binder, a generally iiattened tongue section for impaling apertured sheets thereon, and a cylindrical portion adjacent the enlarged head to provide additional strength in the area of the prong subject to the greatest shock when the binder in which it is used is dropped.

Another object is to provide a sheet retaining prong that may be repeatedly bent at right angles, has a tendency to spring back to straight position immediately upon U release of the bending or holding force, and is adapted to be straightened completely by stroking it between the users fingers.

Another object is to provide sheet retaining prongs with generally flattened tongue sections so shaped that two of them may fit in side by side overlapping relationship in the channel of a conventional prong fastener compressor plate.

The structure by means of which the above noted and other advantages are attained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which:

FIG. 1 is a fragmentary top plan view of a loose leaf binder embodying the invention, showing the top cover in open position and the prong fastener in sheet retaining position;

FIG. 2 is a fragmentary cross sectional view, on an enlarged scale, taken along the line 2--2 of FIG. 1;

FIG. 3 is a fragmentary longitudinal sectional View, on an enlarged scale, taken substantially along the line 3-3 of FIG. l;

FIG. 4 is a detail perspective view of the sheet retaining prong;

FIG. 5 is an enlarged top plan view showing a pair of overlapping prongs in a compressor plate;

FIG. 6 is a cross sectional view taken along the line 6-6 of FIG. 5; and

FIG. 7 is a fragmentary top plan view of a sheet of the type for which the loose leaf binder is intended, showing the row of apertures adjacent one edge thereof.

Referring to the drawings, the reference numeral 2 indicates a bottom cover comprising a sheet 3 of fiber board and a strip 4 of similar material hinged along one edge by strips 5 and 6 of suitable fabric. The strip 4 may be integral with the sheet 3, if desired. A top cover 7 is constructed in the same manner as the bottom cover 2, and comprises a sheet 8 of fiber board and a strip 9 hinged along its corresponding edge by fabric strips 1t) and 11.

A sheet 12 of paper, of the type for which the binder of FIGS. 1, 2 and 3 is intended, is shown in FIG. 7. The sheet 12 is provided with a series of uniformly shaped apertures 13 adjacent one edge thereof. The strip 4 of the bottom cover is provided with a pair of apertures 14 and the strip 9 of the top cover 7 is provided with a pair of apertures 15 adapted to be aligned with the apertures 14. The apertures 1d and 15 are preferably of the same size as the apertures 13, and the spacing between the apertures in the covers is some multiple of the spacing between adjacent apertures 13. When one aperture of each cover is aligned with an aperture 13, the other apertures of the covers are also each aligned with an aperture 13.

The sheet retaining prong 16 is preferably molded of self-lubricating nylon, but may be of any resinous material as hereinabove defined. The prong is a solid onepiece structure comprising an enlarged head 17, a substantially rigid cylindrical shoulder section 13 adjacent said head, and a flexible tongue 19 of generally iiattened cross section having integral reinforcing ribs 20 extending throughout substantially the entire length thereof. The longitudinal ribs 2d also enhance the resilience of the prong and thus increase the tendency of the prong to return to its straight condition immediately after release of any bending or holding force, regardless of the length of time the prong has been held in bent position. If the prong does not return to completely straight condition by reason of its resilience, it may be restored to such condition by stroking it gently between ones fingers.

The longitudinal edges of the prongs are smoothly rounded so that they may be handled without danger of cutting ones fingers. The smoothly rounded longitudinal edges also minimize the possibility of cutting the edegs of the sheet 12 contiguous to the apertures 13 by which the sheets are impaled on the prongs.

The difference between the diameter of the cylindrical section 18 of the prongs and the diameter of the aperture 14 is V64 of an inch. This diffrence provides sufiicient clearance to allow the prongs to be easily inserted into the apertures 14, and is small enough to provide a snug fit and prevent the prongs from wobbling in the apertures. The prong is tapered gradually from the cylindrical section 18 to the generally flattened tongue section 19, as indicated at 21, to provide maximum strength. Preferably the cylindrical section 1S is comparatively short, and is substantially rigid because of its short length. The cylindrical section 13 is short enough so that it will not project any appreciable distance above the bottom cover 2, and even a few sheets may be securely held in the binder.

A compressor plate 22 is positioned above the strip 9 to hold the tongues 19 in sheet retaining position. The compressor plate is preferably conventional, and comprises a fiat metal strip having raised longitudinal edges 23 defining a channel 24 over which keepers 25 are slidably mounted. A narrow slot 26 extends transversely of the channel 24 adjacent each end of the compressor plate and spaced to be aligned with the apertures 14.

After the sheets 12 are impaled on the prongs 16, the cover 7 and the compressor plate 22 are impaled on the prongs, and the tongues 19 are then bent into the channel 24. The keepers 25 are then slid from the center portion of the compressor plate towards the ends until one keeper is over the end of each tongue. The resilience of the tongues 19 urges them upwardly to provide frictional contact with the underside of the keepers, as indicated in FIG. 3, sufiicient to hold the keepers against accidental displacement. The friction is not sufficient to prevent the keepers from moving freely when the prong fastener mechanism is to be opened for the insertion or removal of sheets.

As shown in FIGS. 6 and 7, the tongues of two prongs may fit in the channel of the compressor plate 22 in side by side relationship with their two adjacent longitudinal edges overlapped. The reinforcing ribs 2t) are located centrally of each rib so that each rib is spaced outwardly of the overlapping portions of the tongues. The self-lubricating characteristic of the nylon prongs facilitates the sliding movement of the keepers over the tongues of the prongs which are disposed in the channel of the compressor plate, and also facilitates the movement of the tongues through the apertures of the compressor plate.

Although I have described a preferred embodiment of my invention in considerable detail, it will be understood that the description is intended to be illustrative, rather than restrictive, as many details of the invention may be modified or changed without departing from the spirit or scope of our invention. Accordingly, I do not desire t0 be restricted to the exact structure described, except as limited by the appended claims.

I claim:

1. A solid one-piece flexible type 66 nylon sheet retaining prong comprising a head, an intermediate section and a tongue section, said tongue section having a generally fiattened cross section and an integral longitudinally extending reinforcing rib.

2. A loose leaf binder comprising a pair of cover members provided with aligned apertures and a pair of solid one-piece sheet retaining prongs formed of material having the physical characteristics of type 66 nylon each of said prongs comprising a short cylindrical section fitting closely in one aperture, an integral enlarged head at one end of said cylindrical section, said enlarged head abutting one of said covers to prevent movement of said prong in one direction, a flat flexible tongue projecting from the opposite end of said cylindrical section, said tongues extending through the apertures of said cover member, each of said tongues having an integral longitudinally extending reinforcing rib, each of said tongues being bent at approximately right angles adjacent the aperture through which it extends, and means 5 6 engaging said tongues to prevent accident displacement FOREIGN PATENTS 0f Sald PfOIlgS- 752,929 France July 31, 1933 References cited in the 111e of this patent 5471141 B61911111 May 15 1956 UNITED STATES PATENTS 5 OTHER REFERENCES 1,683,975 Horn Sept. 11, 1928 Polyamide Resins-P1astics Applications Series, by 2,172,374 Flory Sept. 12, 1939 Floyd. 2,280,184 Brennan Apr. 2l, 1942 APC application of Hanns Uier et al., Serial No. 2,321,560 TruSSell June 8, 1943 303,534, published April 20, 1943.

2,612,166 Trusseu sept. 3o, 1952 1 

1. A SOLID ONE-PIECE FLEXIBLE TYPE 66 NYLON SHEET RETAINING PRONG COMPRISING A HEAD, AN INTERMEDIATE SECTION AND A TONGUE SECTION, SAID TONGUE SECTION HAVING A GENERALLY FLATTENED CROSS SECTION AND AN INTEGRAL LONGITUDINALLY EXTENDING REINFORCING RIB. 